diff options
| author | Andy Lutomirski <luto@kernel.org> | 2017-06-29 08:53:18 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-07-05 10:52:57 +0200 |
| commit | 43858b4f25cf0adc5c2ca9cf5ce5fdf2532941e5 (patch) | |
| tree | febc629e329d6918ac4acd3915aa8c2681d8b078 /drivers/idle/intel_idle.c | |
| parent | 94b1b03b519b81c494900cb112aa00ed205cc2d9 (diff) | |
x86/mm: Stop calling leave_mm() in idle code
Now that lazy TLB suppresses all flush IPIs (as opposed to all but
the first), there's no need to leave_mm() when going idle.
This means we can get rid of the rcuidle hack in
switch_mm_irqs_off() and we can unexport leave_mm().
This also removes acpi_unlazy_tlb() from the x86 and ia64 headers,
since it has no callers any more.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Nadav Amit <nadav.amit@gmail.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/03c699cfd6021e467be650d6b73deaccfe4b4bd7.1498751203.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/idle/intel_idle.c')
| -rw-r--r-- | drivers/idle/intel_idle.c | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index 216d7ec88c0c..2ae43f59091d 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -912,16 +912,15 @@ static __cpuidle int intel_idle(struct cpuidle_device *dev, struct cpuidle_state *state = &drv->states[index]; unsigned long eax = flg2MWAIT(state->flags); unsigned int cstate; - int cpu = smp_processor_id(); cstate = (((eax) >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK) + 1; /* - * leave_mm() to avoid costly and often unnecessary wakeups - * for flushing the user TLB's associated with the active mm. + * NB: if CPUIDLE_FLAG_TLB_FLUSHED is set, this idle transition + * will probably flush the TLB. It's not guaranteed to flush + * the TLB, though, so it's not clear that we can do anything + * useful with this knowledge. */ - if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED) - leave_mm(cpu); if (!(lapic_timer_reliable_states & (1 << (cstate)))) tick_broadcast_enter(); |